dom/html/HTMLStyleElement.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6 #include "mozilla/dom/HTMLStyleElement.h"
   7 #include "mozilla/dom/HTMLStyleElementBinding.h"
   8 #include "nsGkAtoms.h"
   9 #include "nsStyleConsts.h"
  10 #include "mozilla/dom/Document.h"
  11 #include "mozilla/dom/FetchPriority.h"
  12 #include "mozilla/dom/ReferrerInfo.h"
  13 #include "nsUnicharUtils.h"
  14 #include "nsThreadUtils.h"
  15 #include "nsContentUtils.h"
  16 #include "nsStubMutationObserver.h"
  17 #include "nsDOMTokenList.h"
  18
  19 NS_IMPL_NS_NEW_HTML_ELEMENT(Style)
  20
  21 namespace mozilla::dom {
  22
  23 HTMLStyleElement::HTMLStyleElement(
  24     already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo)
  25     : nsGenericHTMLElement(std::move(aNodeInfo)) {
  26   AddMutationObserver(this);
  27 }
  28
  29 HTMLStyleElement::~HTMLStyleElement() = default;
  30
  31 NS_IMPL_CYCLE_COLLECTION_CLASS(HTMLStyleElement)
  32
  33 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(HTMLStyleElement,
  34                                                   nsGenericHTMLElement)
  35   tmp->LinkStyle::Traverse(cb);
  36   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mBlocking)
  37 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
  38
  39 NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(HTMLStyleElement,
  40                                                 nsGenericHTMLElement)
  41   tmp->LinkStyle::Unlink();
  42   NS_IMPL_CYCLE_COLLECTION_UNLINK(mBlocking)
  43 NS_IMPL_CYCLE_COLLECTION_UNLINK_END
  44
  45 NS_IMPL_ISUPPORTS_CYCLE_COLLECTION_INHERITED(HTMLStyleElement,
  46                                              nsGenericHTMLElement,
  47                                              nsIMutationObserver)
  48
  49 NS_IMPL_ELEMENT_CLONE(HTMLStyleElement)
  50
  51 bool HTMLStyleElement::Disabled() const {
  52   StyleSheet* ss = GetSheet();
  53   return ss && ss->Disabled();
  54 }
  55
  56 void HTMLStyleElement::SetDisabled(bool aDisabled) {
  57   if (StyleSheet* ss = GetSheet()) {
  58     ss->SetDisabled(aDisabled);
  59   }
  60 }
  61
  62 void HTMLStyleElement::CharacterDataChanged(nsIContent* aContent,
  63                                             const CharacterDataChangeInfo&) {
  64   ContentChanged(aContent);
  65 }
  66
  67 void HTMLStyleElement::ContentAppended(nsIContent* aFirstNewContent) {
  68   ContentChanged(aFirstNewContent->GetParent());
  69 }
  70
  71 void HTMLStyleElement::ContentInserted(nsIContent* aChild) {
  72   ContentChanged(aChild);
  73 }
  74
  75 void HTMLStyleElement::ContentRemoved(nsIContent* aChild,
  76                                       nsIContent* aPreviousSibling) {
  77   ContentChanged(aChild);
  78 }
  79
  80 void HTMLStyleElement::ContentChanged(nsIContent* aContent) {
  81   mTriggeringPrincipal = nullptr;
  82   if (nsContentUtils::IsInSameAnonymousTree(this, aContent)) {
  83     Unused << UpdateStyleSheetInternal(nullptr, nullptr);
  84   }
  85 }
  86
  87 nsresult HTMLStyleElement::BindToTree(BindContext& aContext, nsINode& aParent) {
  88   nsresult rv = nsGenericHTMLElement::BindToTree(aContext, aParent);
  89   NS_ENSURE_SUCCESS(rv, rv);
  90   LinkStyle::BindToTree();
  91   return rv;
  92 }
  93
  94 void HTMLStyleElement::UnbindFromTree(UnbindContext& aContext) {
  95   RefPtr<Document> oldDoc = GetUncomposedDoc();
  96   ShadowRoot* oldShadow = GetContainingShadow();
  97
  98   nsGenericHTMLElement::UnbindFromTree(aContext);
  99
 100   Unused << UpdateStyleSheetInternal(oldDoc, oldShadow);
 101 }
 102
 103 bool HTMLStyleElement::ParseAttribute(int32_t aNamespaceID, nsAtom* aAttribute,
 104                                       const nsAString& aValue,
 105                                       nsIPrincipal* aMaybeScriptedPrincipal,
 106                                       nsAttrValue& aResult) {
 107   if (aNamespaceID == kNameSpaceID_None && aAttribute == nsGkAtoms::blocking &&
 108       StaticPrefs::dom_element_blocking_enabled()) {
 109     aResult.ParseAtomArray(aValue);
 110     return true;
 111   }
 112
 113   return nsGenericHTMLElement::ParseAttribute(aNamespaceID, aAttribute, aValue,
 114                                               aMaybeScriptedPrincipal, aResult);
 115 }
 116
 117 void HTMLStyleElement::AfterSetAttr(int32_t aNameSpaceID, nsAtom* aName,
 118                                     const nsAttrValue* aValue,
 119                                     const nsAttrValue* aOldValue,
 120                                     nsIPrincipal* aSubjectPrincipal,
 121                                     bool aNotify) {
 122   if (aNameSpaceID == kNameSpaceID_None) {
 123     if (aName == nsGkAtoms::title || aName == nsGkAtoms::media ||
 124         aName == nsGkAtoms::type) {
 125       Unused << UpdateStyleSheetInternal(nullptr, nullptr, ForceUpdate::Yes);
 126     }
 127   }
 128
 129   return nsGenericHTMLElement::AfterSetAttr(
 130       aNameSpaceID, aName, aValue, aOldValue, aSubjectPrincipal, aNotify);
 131 }
 132
 133 void HTMLStyleElement::GetInnerHTML(nsAString& aInnerHTML,
 134                                     OOMReporter& aError) {
 135   if (!nsContentUtils::GetNodeTextContent(this, false, aInnerHTML, fallible)) {
 136     aError.ReportOOM();
 137   }
 138 }
 139
 140 void HTMLStyleElement::SetInnerHTML(const nsAString& aInnerHTML,
 141                                     nsIPrincipal* aScriptedPrincipal,
 142                                     ErrorResult& aError) {
 143   SetTextContentInternal(aInnerHTML, aScriptedPrincipal, aError);
 144 }
 145
 146 void HTMLStyleElement::SetTextContentInternal(const nsAString& aTextContent,
 147                                               nsIPrincipal* aScriptedPrincipal,
 148                                               ErrorResult& aError) {
 149   // Per spec, if we're setting text content to an empty string and don't
 150   // already have any children, we should not trigger any mutation observers, or
 151   // re-parse the stylesheet.
 152   if (aTextContent.IsEmpty() && !GetFirstChild()) {
 153     nsIPrincipal* principal =
 154         mTriggeringPrincipal ? mTriggeringPrincipal.get() : NodePrincipal();
 155     if (principal == aScriptedPrincipal) {
 156       return;
 157     }
 158   }
 159
 160   const bool updatesWereEnabled = mUpdatesEnabled;
 161   DisableUpdates();
 162
 163   aError = nsContentUtils::SetNodeTextContent(this, aTextContent, true);
 164   if (updatesWereEnabled) {
 165     mTriggeringPrincipal = aScriptedPrincipal;
 166     Unused << EnableUpdatesAndUpdateStyleSheet(nullptr);
 167   }
 168 }
 169
 170 void HTMLStyleElement::SetDevtoolsAsTriggeringPrincipal() {
 171   mTriggeringPrincipal = CreateDevtoolsPrincipal();
 172 }
 173
 174 Maybe<LinkStyle::SheetInfo> HTMLStyleElement::GetStyleSheetInfo() {
 175   if (!IsCSSMimeTypeAttributeForStyleElement(*this)) {
 176     return Nothing();
 177   }
 178
 179   nsAutoString title;
 180   nsAutoString media;
 181   GetTitleAndMediaForElement(*this, title, media);
 182
 183   return Some(SheetInfo{
 184       *OwnerDoc(),
 185       this,
 186       nullptr,
 187       do_AddRef(mTriggeringPrincipal),
 188       MakeAndAddRef<ReferrerInfo>(*this),
 189       CORS_NONE,
 190       title,
 191       media,
 192       /* integrity = */ u""_ns,
 193       /* nsStyleUtil::CSPAllowsInlineStyle takes care of nonce checking for
 194          inline styles. Bug 1607011 */
 195       /* nonce = */ u""_ns,
 196       HasAlternateRel::No,
 197       IsInline::Yes,
 198       IsExplicitlyEnabled::No,
 199       FetchPriority::Auto,
 200   });
 201 }
 202
 203 JSObject* HTMLStyleElement::WrapNode(JSContext* aCx,
 204                                      JS::Handle<JSObject*> aGivenProto) {
 205   return HTMLStyleElement_Binding::Wrap(aCx, this, aGivenProto);
 206 }
 207
 208 nsDOMTokenList* HTMLStyleElement::Blocking() {
 209   if (!mBlocking) {
 210     mBlocking =
 211         new nsDOMTokenList(this, nsGkAtoms::blocking, sSupportedBlockingValues);
 212   }
 213   return mBlocking;
 214 }
 215
 216 bool HTMLStyleElement::IsPotentiallyRenderBlocking() {
 217   return BlockingContainsRender();
 218
 219   // TODO: handle implicitly potentially render blocking
 220   // https://html.spec.whatwg.org/#implicitly-potentially-render-blocking
 221   // A style element is implicitly potentially render-blocking if the element
 222   // was created by its node document's parser.
 223 }
 224
 225 }  // namespace mozilla::dom